Regulator apparatus

ABSTRACT

A regulator for electrical heat energy apparatus including a base and a spindle rotatably mounted to the base. On the spindle there is a cam which is mounted in the same direction as the operative force applied to the cam such that the force tends to hold the cam in position. Preferably, the spindle is mounted in a bush integral with the base and which fits through an opening in the apparatus to which the regulator is fitted.

Umted States Patent [1 1 u 11 3, Speedie Dec. 23, 1975 REGULATOR APPARATUS 3,]42J87 7/1964 Kane at al 74/56 x Inventor: Robert 8 Carnegie, ra ia 3.27l,531 9/1966 Winogrockl et a] 200/6 B [73:] Assignee: Illinois Tool Works Inc., Chicago, i Examiner samuel Scott Assistant Examiner-F. D. Shoemaker [22] Filed: M3 17, 1974 Attorney, Agent, or Firm-Robert W. Beart; Jack R.

l 211 Appl. No.: 470,878 Ha 30 Foreign Application Priority Data [57] ABSTRACT May 23, I973 Australia 3418/73 A g ator for electrical heat energy apparatus including a base and a spindle rotatably mounted to the [52] US. Cl. 74/567; 200/ 153 L as on the spindle h r s a am h h s m unt d [5 I] Int. Cl. F1611 53/00 in h m ir ion s h op rative for ppli to [58] Field of Search 74/567, 55; 200/6 B, 6 BB, the cam such that the force tends to hold the cam in 200/30 R, I53 L, 291 position. Preferably, the spindle is mounted in a bush integral with the base and which fits through an open- [56] References Cited ing in the apparatus to which the regulator is fitted.

UNITED STATES PATENTS l3 Claim 5 Drawing Figures 2,848,584 8/!958 Goudy et a]. 200/291 wJ/Zg 37 39 l 3435 32 Z2 5 REGULATOR APPARATUS This invention relates to regulator or control apparatus and it refers particularly but not exclusively to the construction and assembly of electrical energy regulators such as temperature control means for electric hot plates and so on.

It is an object of the invention to provide a construction of regulator apparatus of the type indicated which will be economical to manufacture and assembly and which will be more positive in action than such regulators as hitherto made. Another object is to provide a regulator apparatus having a relatively small number of parts and which will be easy to assemble. A further object isto provide a regulator apparatus of such design and construction as to provide for accuracy of operation, ease of assembly and economy of production.

According to present practice the actuating cam in the regulator apparatus for controlling the temperature of electric hot plates and the like electrical apparatus is mounted in a base block and is secured to a metal spindle which is rotatably mounted in a metal bush held in position by a retaining bracket. The retaining bracket and bush are insulated from the base block by an insulating board. In one known form of the apparatus the actuating cam is assembled into the base block in a direction opposite to the direction of application of force by the apparatus to be actuated, and it is necessary to provide spring means between the cam and the insulating board to resist the thrust applied. In another form the cam operates against a radial actuating force and therefore it is not necessary to provide the spring means.

However, in both these forms there is some difficulty in construction and/or assembly of the parts and there is the difficulty in insulating the parts so as to avoid danger to the person who operates the apparatus.

Another object is to provide an improved construction of control apparatus for actuating means such as {lie temperature control of electric hot plates and the According to one aspect of the invention there is provided a regulator or control apparatus having a base block incorporating means whereby it may be mounted securely in position, and cam means on a spindle mounted in the base block so as to be rotatable about its central longitudinal axis, the cam means being capable of being mounted in the base block in the same direction as the direction of the force applied to the cam means when in operation, such that said force tends to hold the cam means in its seating in the base block. I

In another aspect of the invention the regulator or control apparatus has a base block with an integral bush member for fitting through an opening in a panel or other member to which the regulator apparatus is to I C be fitted, the base block and bush member being of electrical insulating material, and actuating cam nonrotatable relative to an operating spindle which is rotatably mounted in the bush member, said cam being mounted to bear upon an inner surface of the base block and said spindle being held against movement to disengage it from the bush member. Preferably, the bush member has a part operative to engage with a complementary part of the spindle when said spindle is pressed into the bush in order to hold the spindle against return movement, and in operative position.

Preferably, in this latter construction, the bush member is externally screw threaded to permit engagement by a nut, for locking the base block in its operating position, and the cam is engaged in a recess in the base of the base block.

It is also preferred that there be provided a cover having at least one finger member for engagement with a complementary part of the base block in such manner that once the cover is pressed into closed position the at least one finger member is securely engaged with the complementary part in such manner that opening of the cover will be strongly resisted, so as to make dlfficult the tampering with the apparatus under the cover.

In order that the invention will be clearly understood and readily put into practical form there will now be described with reference to the accompanying illustrative drawings a preferred construction of apparatus made according to the invention. In these drawings:

FIG. 1 is a perspective view of the base block, from the top or outer side;

FIG. 2 is a perspective view of the base block, from the bottom or under side;

FIG. 3 shows the cover in perspective, from the under side;

FIG. 4 is a cross-section through the regulator assembly, the section being on a plane as indicated by the line and arrows 4-4 in FIG. 1, through the longitudinal central axis of the spindle [which is shown in full, not m cross-section}; and

FIG. 5 is another cross-sectional view through part of the regulator assembly, the section being on a plane as indicated by the line and arrows 5-5 in FIG. I, through the longitudinal central axis of the spindle at right angles to the plane of FIG. 4.

The base block 11 has two opposite ends 12, two opposite sides 13 with extensions 14 cut away at 15 on the underside thereof and provided with openings 16 therethrough, a base 17 with an integral externally screw-threaded bush [8 extending from its underside, the bush 18 having at its outer end an inwardly tapered extension 19, two spigots 20 on the underside of the base 17 for holding the base block 11 against rotation, at co-axial bore or passageway 21 through the base 17 and bush 18 for receiving the operating spindle, a shaped recess 22, 23 in the inner surface of the base l8 about the bore or passageway 21 to provide a seating for the actuating cam and to accommodate a spring, and other shaped recesses projections 24, 25, 26 for the mounting in the base block of the apparatus (not shown) to be controlled or regulated by this regulator apparatus.

The cover 28 is made to fit on the outer side of the base block 11 and it has a top, four sides and two oppositely disposed fingers 29 adapted to engage in the openings 16 in the side extensions 14, said fingers having outwardly extending projections 30 adapted to engage in the cut-away portions 15 to grip under the extension parts 14 and thereby hold the cover in POSI- tioh. Once the cover 28 has been pressed into engagement with the base block ll, the fingers 29 engaging in the openings 16 with the projections 30 engaged in the cut-away portions 15, the cover 28 will be held securely in position and removal thereof without special tools for releasing the fingers 29 will be difficult.

The actuating cam 32 has a substantially cylindrical part 33 adapted to seat for rotational movement in the recess 22 in the base 17, and at its outer end part there is an external flange 34 and a ramp-type cam face 35 for actuating a control member 37 indicated in FIGS. 4 and 5. The cam 32 has a non-circular recess in its outer end part and an axial hole for accommodating tightly the head 39 (of the same shape as the recess) and part of the shank of an operating spindle 40. Said spindle has a circumferential groove 41 for receiving the tapered extension 19 of the bush l8, and at its outer end there is provision for fastening thereto a knob or finger piece 43.

The base block 11 and bush l8 integral therewith are preferably made as a unitary moulding, and are made of an electrical insulating material of somewhat resilient character. The cover 28, cam 32 and finger piece 43 are also made of electrical insulating materials, such as synthetic plastic materials. The spindle 40 may be made of metal.

In the assembly of the parts the cam 32 is first pressed on to the spindle 40 so that the head 39 of said spindle is firmly engaged in the recess in the outer end of the cam, thereby ensuring that the cam 32 is non-rotatable relative to the spindle. Then the spindle is pressed into the bore or passageway 21 in the base 17 and bush 18 so that the cam part 33 seats in the recess 22 in the base 17 and the tapered extension 19 of the bush [8 snaps into engagement in the groove 41 in the spindle 40 so as to hold the spindle against movement in the reverse direction. A spring 45 is mounted in the recess part 23 in the base 17 so as to bear upon the lower part 33 of the cam.

Next, the apparatus to be actuated is mounted in or on the base block 11, and the cover 28 is snapped into engagement with the base block ll.

Then the assembly of the base block 11, cam 32, operating spindle 40, apparatus to be actuated and cover 28 is mounted in a panel or other support indicated by the reference A with the spigots 20 engaged in appropriate locating holes, a nut B is screwed on to the bush 18 so as to secure the assembly in position, and the finger piece 43 is fastened to the outer end of the spindle 40.

If desired, the cam part 33 may be provided with circumferentially spaced indentations and the spring 45 may be made as a detent to engage therein, providing a number of stations to which the cam may be turned selectively.

It is to be noted that as the actuating cam 32 seats against the bottom of the recess 22 in the base block 11 the force applied to the cam 32 by the member 37 tends to press the cam into its seating and there is a positive engagement between the operating parts. Due to the engagement of the bush extension 19 in the groove 4] in the spindle the cam -spindle assembly is held in assembled relationship before the assembly into the base block 11 of the mechanism to be actuated by the cam 32.

Further, as the base block 1] and bush 18 are made as a unitary moulding of an electrical insulating material, as a suitable synthetic plastic material, there is no need to provide an insulating board between the base block 11 and the support A, as has been required in the past.

The apparatus provided by this invention is of simple character but it provides a marked advance over the apparatus hitherto provided.

It is to be understood that modifications in details of construction and design may be made without departing from the ambit of the invention as defined by the appended claims. Thus, in some cases it may be considered convenient to have the spindle assembled into the base block and into the cam from the opposite direction, the cam 32 being previously located in the recess 22. In such a case there may be provided means in both the cam 32 and the base block 11 to hold the spindle 40 against withdrawal whilst permitting it to have rotational movement in the bush 18.

I claim:

1. In a regulator apparatus having a base block, a bush member formed integrally with the base block as an extension from the underside thereof and having an external screw thread engageable by a nut to secure the base block in its operating position, a cam means and a spindle, the cam means being mounted on the spindle and the spindle being mounted in the base block and further being rotatable about its central longitudinal axis; the improvement wherein the cam means is mounted in the same direction as the force applied to it when in operation such that the force tends to hold the cam means in a seating in the base block.

2. A regulator as claimed in claim 1 wherein there is further provided a recess in the inner side of the base of the base block accommodating the cam means for rotational movement, and a face cam on said cam means for actuating a control member in a linear direction parallel to the axis of rotation of the cam means.

3. A regulator as claimed in claim 2 wherein a spring is provided in the recess to bear against the cam means.

4. A regulator as claimed in claim 1 wherein there is provided a cover engageable with the base block so as to enclose its open upper side and co-operating locking means between the cover and the base block to secure the cover in position.

5. A regulator as claimed in claim 4, wherein the co-operating locking means comprises at least one finger member on the cover having an outwardly directed projection, the base block has at least one opening engageable by the finger member of the cover, and the side walls in said openings are shaped for locking engagement by the projections of said fingers.

6. A regulator apparatus having a base block with an integral bush member for fitting through an opening in a member to which the regulator apparatus is to be fitted, an actuating cam non-rotatable relative to an operating spindle rotatably mounted in the bush member, the cam being mounted to bear upon an inner surface of the base block and said spindle being held against movement to disengage it from the bush memher.

'7. A regulator apparatus as claimed in claim 6 wherein the base block and the bush member are of an electrical insulating material.

8. A regulator apparatus as claimed in claim 7 wherein the bush member has a part engageable with a complementary part of the spindle when the spindle is pressed into the bush in order to hold the spindle in its operative position and against return movement.

9. A regulator apparatus as claimed in claim 8 wherein the bush member is screw threaded externally, the screw threads being engageable by a nut so as to secure the base block in its operating position.

10. A regulator as claimed in claim 6 wherein a spring is provided in the recess to bear against the actuating cam.

11. A regulator apparatus as claimed in claim 10 wherein there is provided a cover engageable with the base block so as to enclose its open upper side and co-operating locking means between the cover and base block to secure the cover in position.

12. A regulator apparatus as claimed in claim ll wherein the co-operating locking means comprises at least one finger member on the cover having an outwardly directed projection, the base block has at least one opening engageable by the finger member of the cover, and the side walls in said openings are shaped for locking engagement by the projections of said fingers.

13. A regulator apparatus having a base block having an integral bush member extending from the underside thereof, the bush member having an external screw thread engageable by a nut so as to secure the base block in its operating position; an actuating cam mounted on a spindle, the spindle being mounted in the base block and the bush member and being rotatable about its central longitudinal axis, the actuating cam being accommodated in a recess in the base of said base block and being rotatable relative to said base block, the cam actuating a control member in a linear direction parallel to the axis of rotation of the cam; a spring mounted in a recess in the base block and engaging the actuating cam; and a cover engageable with the base block so as to enclose its open upper side.

i i i 

1. In a regulator apparatus having a base block, a bush member formed integrally with the base block as an extension from the underside thereof and having an external screw thread engageable by a nut to secure the base block in its operating position, a cam means and a spindle, the cam means being mounted on the spindle and the spindle being mounted in the base block and further being rotatable about its central longitudinal axis; the improvement wherein the cam means is mounted in the same direction as the forCe applied to it when in operation such that the force tends to hold the cam means in a seating in the base block.
 2. A regulator as claimed in claim 1 wherein there is further provided a recess in the inner side of the base of the base block accommodating the cam means for rotational movement, and a face cam on said cam means for actuating a control member in a linear direction parallel to the axis of rotation of the cam means.
 3. A regulator as claimed in claim 2 wherein a spring is provided in the recess to bear against the cam means.
 4. A regulator as claimed in claim 1 wherein there is provided a cover engageable with the base block so as to enclose its open upper side and co-operating locking means between the cover and the base block to secure the cover in position.
 5. A regulator as claimed in claim 4, wherein the co-operating locking means comprises at least one finger member on the cover having an outwardly directed projection, the base block has at least one opening engageable by the finger member of the cover, and the side walls in said openings are shaped for locking engagement by the projections of said fingers.
 6. A regulator apparatus having a base block with an integral bush member for fitting through an opening in a member to which the regulator apparatus is to be fitted, an actuating cam non-rotatable relative to an operating spindle rotatably mounted in the bush member, the cam being mounted to bear upon an inner surface of the base block and said spindle being held against movement to disengage it from the bush member.
 7. A regulator apparatus as claimed in claim 6 wherein the base block and the bush member are of an electrical insulating material.
 8. A regulator apparatus as claimed in claim 7 wherein the bush member has a part engageable with a complementary part of the spindle when the spindle is pressed into the bush in order to hold the spindle in its operative position and against return movement.
 9. A regulator apparatus as claimed in claim 8 wherein the bush member is screw threaded externally, the screw threads being engageable by a nut so as to secure the base block in its operating position.
 10. A regulator as claimed in claim 6 wherein a spring is provided in the recess to bear against the actuating cam.
 11. A regulator apparatus as claimed in claim 10 wherein there is provided a cover engageable with the base block so as to enclose its open upper side and co-operating locking means between the cover and base block to secure the cover in position.
 12. A regulator apparatus as claimed in claim 11 wherein the co-operating locking means comprises at least one finger member on the cover having an outwardly directed projection, the base block has at least one opening engageable by the finger member of the cover, and the side walls in said openings are shaped for locking engagement by the projections of said fingers.
 13. A regulator apparatus having a base block having an integral bush member extending from the underside thereof, the bush member having an external screw thread engageable by a nut so as to secure the base block in its operating position; an actuating cam mounted on a spindle, the spindle being mounted in the base block and the bush member and being rotatable about its central longitudinal axis, the actuating cam being accommodated in a recess in the base of said base block and being rotatable relative to said base block, the cam actuating a control member in a linear direction parallel to the axis of rotation of the cam; a spring mounted in a recess in the base block and engaging the actuating cam; and a cover engageable with the base block so as to enclose its open upper side. 